The present disclosure relates to a wind turbine, and more particularly to a wind turbine rotor having a shell construction.
A common goal for commercial wind-turbine manufacturers is to design and produce a wind-turbine that provides the lowest possible cost of energy (COE) throughout the operational life of a wind-turbine. The COE is determined by a comparison of total yearly costs to yearly energy produced. Thus, the COE is minimized by lowering turbine cost while simultaneously increasing the yearly energy capture.
Wind turbines with 2-bladed rotors may offer weight and cost advantages over three-bladed rotors which are typically used with large, multi-megawatt turbines. One issue with conventional 2-bladed rotors has been noise emissions. Each individual blade in conventional 2-bladed rotors is typically comparable in solidity, e.g. blade chord, to blades on 3-bladed rotors. Consequently, peak rotor efficiency of the 2-bladed rotors is obtained at relatively higher tip-speed ratios, which results in high tip velocity and the associated increase in noise emissions.
Three-bladed rotors are sometimes requested when factors such as optical appeal outweigh cost savings. To allow the option of a two or three bladed rotor, a turbine manufacturer is required to design and produce two different wind turbines which share few common elements. Consequently, the manufacturing, inventory, packaging and other costs are increased.
It is thus desirable to provide a turbine design which provides for a two or three bladed rotor with significant commonality.